Yamato battleship was the lead ship of the Yamato class of Imperial Japanese Navy during the Second World War.

Named after the ancient Japanese Yamato Province, on the Kii peninsula, she was the first of four designed ships and was the heaviest, largest and most powerful battleship ever built, displacing about 72000 tons at full load and armed with nine 46 cm Type 94 main guns. Yamato exceeded other country battleships not only by the displacement and the calibre of her guns, but also by the construction of her hull, armour protection, gunnery and optics. The superiority of her optic equipment gave her tremendous precision to her main gunfire. She was an incredible achievement for the Japanese naval engineering and ship-building industry by any international standard.

DesignYamato was laid down in 1937 and commissioned a week after the Pearl Harbor attack, in late 1941. She served as the flagship of the Japanese Combined Fleet throughout 1942. In June 1942 Admiral Isoroku Yamamoto directed the fleet from Yamato during the Battle of Midway. But after the defeat and the loss of four aircraft-carriers he was forced to return to the Inland Sea. Yamato was designed to counter the numerically superior battleship fleet of the United States of America, but she never in fact fought against them. The only time she fired her main guns against enemy surface targets was in October 1944 during the Battle of Leyte Gulf, but it turned out to be just the US escort carriers and destroyers. During 1944, the balance between naval powers in the Pacific turned against Japan. Soon its fleet was depleted by fuel lack. To slow down the Allied advance, in April 1945, Yamato was dispatched on a “kamikaze” mission to Okinawa. The orders were to fight to the death in a desperate attempt to protect Japan. On 7 April 1945 she was sunk by American carrier-based bombers and torpedo bombers. Most of her crew died.

Design The Washington Treaty of 1922, with his prohibitions on the building of new battleships, held back Japanese projects for the development of the Fleet, which comprised the building of eight modern battle-cruisers and eight modern battleships. The japanese designers and engineers wished to build new high quality units. They considered the US Navy a potential opponent and wanted to ensure that their ship would be stronger and better armed than the US ships. Despite treaty prohibitions, the Bureau of Naval Construction carried on with their studies about the building of battleships and in 1930 they reached a new phase of development. In 1934 Japan withdrew from the League of Nations, renouncing its treaty obligations. In October 1934 the Bureau of Naval Construction received from the Naval General Staff the order to produce a design study of a new battleship with 46 cm guns and a speed of 30 knots. The vessels of the Yamato class were designed to be capable of engaging multiple enemy battleships at the same time. After numerous tests and experiments, a big bulbous was placed at the bow to reduce resistance and improve speed. A bulbous of such a size and shape was unique at that time. In addition the hull had a shallow draught for a ship with such large displacement; so Yamato, and Musashi too, could use the naval base and dry docks of Imperial Japanese Navy as they was, without dredging or rebuilding.

To increase the hull strength, and at the same time, reduce its weight, a new and innovative method was introduced. The armor plating was an integral part of the hull construction and not only an added protection. So the thickness and rigidity of the armour plating reinforced the hull strength too. The characteristic shape of the stern resulted by the necessity of placing the hawse pipes away from the ship’s centre line to protect the bulbous bow from anchors. Boats, planes and other equipment were placed in protected magazines and hangars to protect them from being damaged by the terrific blast of the 46 cm guns. In fact the blast pressure of this weapon was capable of destroying boats or tearing the clothing from crew and making them unconscious. So ventilation openings were placed in strategic way to reduce or avoid the effect of the blast.

Yamato had a length of 256 meters between perpendiculars and 263 meters overall. She had a beam of 38.9 meters and a draft of 11 meters at deep load. She displaced 64000 long tons at standard load and about 72000 tons at deep load. Her crew consisted of 2500-2800 officers and men, however, in the last battle it consisted of 3332. She had four sets of Kampon geared steam turbines, each of which drove one propeller shaft. The turbines were designed to produce a total of 150000 shat horsepower (110000 kW), using steam provided by 12 Kampon water-tube boilers, to give her a maximum speed of 27 knots (50 km/h). She had a storage capacity of 6300 long tons of fuel oil, giving her a range of 7200 nautical miles (13300 km) at a speed of 16 knots (30 km/h)

Armour The total weight of Yamato’s armour protection was 22895 tons. The heaviest armour protection ever built in the history. The main belt of armour along the side, at waterline, was 410 millimeters thick and angled outwards 20 degrees at the top. Beyond the main belt there were additional bulkheads 335 millimeters thick. Below there was a strake of armour that ranged in thickness from 270 to 200 millimeters over the magazines and machinery spaces respectively; it tapered to a thickness of 75 millimeters at its bottom edge. The deck armour ranged in thickness from 230 to 200 millimeters. The turrets were protected with an armour of 650 millimeters thick on the face, 250 millimeters on the sides, and 270 millimeters on the roof. The barbettes of the turrets were protected by 560 to 280 millimeters thick armour, and the turrets of the 155 mm guns were protected by 50 millimeters armour plates. The sides of the conning tower were protected by 500 millimeters thick armour and the roof had a 200 millimeters thick plate. The floors of the ammunition magazines were protected by 50 to 80 millimeters armour plates which extended from the bottom of the magazines and across water-tight compartments above the double bottom of the hull’s shell; this would have protected the magazines from the explosion of a hostile torpedo or mine beneath the ship.